Effects of Marathon Training on Male and Female Femoral Stress Fracture Risk

Marathon runners are prone to femoral stress fractures due to the high magnitudes and frequencies of lower extremity loads during training. Female runners tend to have a greater incidence of stress fracture compared to male runners. Sex-specific differences in body structure, joint pressure, and muscle activation patterns that influence bone remodeling may cause this observed difference in stress fracture occurrence. The goal of this thesis was to develop a finite element model of the femur during marathon training, then determine if marathon training affected bone properties of male and female runners differently. To achieve this goal, a finite element femur model was integrated with a bone remodeling algorithm. Sex-specific muscle and joint pressure loads corresponding to baseline activity and marathon training were applied to the finite element femur model. Axial strain, density, damage, and remodeling activity were quantified at regions predicted to be at high risk of stress fracture. The major results of this analysis predicted that marathon training increased bone damage at all regions of interest in both males and females, especially at the inferior neck. The model predicted that the superior neck, trochanter, and proximal diaphysis were more severely weakened in females than males after marathon training. While this model cannot directly quantify femoral stress fracture risk, it may be used to predict regions of bone weakness in male and female marathon runners. Future work may be done to improve accuracy of this model by using sex-specific femur geometry and bone remodeling parameters specific to male and female marathon runners. This model may be useful in future applications to study effectiveness of injury preventive methods, such as gait retraining, in reducing bone damage

Leadership and Agency as a Novice Teacher

Tells an inspiring tale of a new teacher who refused to accept the dreary status quo to which beginning professionals are so often consigned. Almost in anger at the assumption that she was supposed to be miserable for her whole first year, she struggled mightily to find innovative ways to solve her most intractable classroom problems, and then turned her energies to whole-school reform

Gender equality and plan making: Gender mainstreaming toolkit

Report produced for RTP

Noble gases and stable isotopes in a shallow aquifer in southern Michigan: Implications for noble gas paleotemperature reconstructions for cool climates

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95038/1/grl20200.pd

The relationship between cation exchange capacity, total bases, and exchange acidity in certain Oregon soils

Two soils representative of the coast and three representing the Willamette Valley have been studied for their general chemical characteristics. Exchange capacity and exchangeable cations were determined by the ammonium acetate and the BaCl₂-triethanolamine buffer methods. Exchange capacity was also obtained from conductimetric titrations which were run on each soil before and after destroying the organic matter.Potentiometric titrations were run before and after leaching each soil with HCl. Lime requirement was determined by Woodruff's method and also obtained from the pH-lime curves. The two coastal soils, Astoria and Clatsop, have lower pH and base saturation and higher organic matter content and exchange capacity than the Melbourne, Olympic, and Willamette soils from the valley. The Melbourne soil had the highest base saturation percentage and Astoria had the lowest. The amount of exchangeable aluminum was also higher in the coastal soils. The amount of exchange capacity contributed to the organic fraction was 65 per cent in the Olympic and Willamette soils and 50 per cent in the other three. The value for exchange capacity by the different methods was in good agreement in the three valley soils before and after the organic matter was destroyed. In the coastal soils there was no agreement between methods in any case. This would indicate that in the latter two soils, type of clay mineral present may be more of an influence than in the former soils. The potentiometric titration curves showed that the two coastal soils were well buffered and the valley soils were only slightly buffered. After the soils were leached with HCl the Melbourne soil was the only one which indicated a strong acid property. The exchange properties of the soils as affected by additions of lime were studied by incubating the soils for four weeks with added increments of lime. With each added increment of lime the pH increased and exchangeable acidity decreased in each soil. The amount of lime to bring the soils to any given degree of base saturation appeared to be proportional to the magnitude of the exchange capacity and inversely proportional to the degree of base saturation. At any given pH value there was a considerable difference in the degree of base saturation for these soils. This might well be a reflection of the type of minerals present in the different soils. More lime was required to bring the two coastal soils up to pH 6.5 as indicated by the pH-lime relationship curve than that estimated by the Woodruff method. Consistent results were observed in the three valley soils. This suggests that the buffer solution at pH 7 as recommended by Woodruff was not strong enough to neutralize the acidity in the coastal soils. There was good agreement between the two methods in the determination of the exchangeable bases. The BaCl₂-buffer method gave much higher values of exchangeable acidity than did the ammonium acetate method. These values, when converted to tons of calcium carbonate, agree fairly closely with the amount of lime required to bring the soils to pH 7 when added directly to the soil. When lime was added above the saturation point the amount of exchangeable calcium as determined by the ammonium acetate method increased but remained relatively constant for the BaCl₂-buffer method. The various analysis seem to indicate that the Astoria and Clatsop soils contain predominantly 2:1 type clay minerals while the Olympic and Willamette soils contain predominantly the 1:1 type. The Melbourne soil exhibits properties more closely associated with the coastal soils

Evidence of abundant stop codon readthrough in Drosophila and other Metazoa

While translational stop codon readthrough is often used by viral genomes, it has been observed for only a handful of eukaryotic genes. We previously used comparative genomics evidence to recognize protein-coding regions in 12 species of Drosophila and showed that for 149 genes, the open reading frame following the stop codon has a protein-coding conservation signature, hinting that stop codon readthrough might be common in Drosophila. We return to this observation armed with deep RNA sequence data from the modENCODE project, an improved higher-resolution comparative genomics metric for detecting protein-coding regions, comparative sequence information from additional species, and directed experimental evidence. We report an expanded set of 283 readthrough candidates, including 16 double-readthrough candidates; these were manually curated to rule out alternatives such as A-to-I editing, alternative splicing, dicistronic translation, and selenocysteine incorporation. We report experimental evidence of translation using GFP tagging and mass spectrometry for several readthrough regions. We find that the set of readthrough candidates differs from other genes in length, composition, conservation, stop codon context, and in some cases, conserved stem–loops, providing clues about readthrough regulation and potential mechanisms. Lastly, we expand our studies beyond Drosophila and find evidence of abundant readthrough in several other insect species and one crustacean, and several readthrough candidates in nematode and human, suggesting that functionally important translational stop codon readthrough is significantly more prevalent in Metazoa than previously recognized.National Institutes of Health (U.S.) (U54 HG00455-01)National Science Foundation (U.S.) (CAREER 0644282)Alfred P. Sloan Foundatio

Reply to comment by Klump et al. on “Noble gases and stable isotopes in a shallow aquifer in southern Michigan: Implications for noble gas paleotemperature reconstructions for cool climates”

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94860/1/grl22429.pd

Wide Field-of-View, Large-Area Long-wave Infrared Silicon Metalenses

Long-wave infrared (LWIR, 8-12 $\mu m$ wavelengths) is a spectral band of vital importance to thermal imaging. Conventional LWIR optics made from single-crystalline Ge and chalcogenide glasses are bulky and fragile. The challenge is exacerbated for wide field-of-view (FOV) optics, which traditionally mandates multiple cascaded elements that severely add to complexity and cost. Here we designed and experimentally realized a LWIR metalens platform based on bulk Si wafers featuring 140$^\circ$ FOV. The metalenses, which have diameters exceeding 4 cm, were fabricated using a scalable wafer-level process involving photolithography and deep reactive ion etching. Using a metalens-integrated focal plane array, we further demonstrated wide-angle thermal imaging